tolong jawab beserta caranya

f (x) = u/ V
f '(x) = (u'.v - u.v') / v^2
= (-sin x. sin x - (1+cos.x). cos x ) / sin^2 x
= (-sin^2 x - cos x - cos^2 x ) / sin^2 x
= { - (sin^2 x + cos^2 x) - cos x } / sin^2 x
= ( -1 - cos x) / sin^2 x
= - (1 + cos x)/(1- cos^2 x)
= -(1+ cos x)/(1+cos x)(1- cos x)
= - 1/(1 - cos x)
= - 1 / -(cos x - 1)
= 1 / (cos x - 1)....(E)